🔥 Shingrix Vaccine Efficacy Simulator

Dose 1 — Priming the Immune System

The first injection introduces the response.

• Recombinant: Vaccine type (gE antigen + AS01B adjuvant)
• IM: Route (deltoid muscle)
• 0%: Baseline titer (pre-vaccination)
• AS01B: Adjuvant (liposome-based)

What happens at dose 1

Placeholder: dose 1 introduces antigen and adjuvant to trigger priming.

Initial Immune Response Building

Titers rise over the first weeks after dose 1.

• ~Week 4: Peak (dose 1) (partial response)
• CD4+ T-cell: Response type (plus antibody titer)
• Partial: Protection level (single-dose only)
• ~Month 2: Decline onset (without dose 2)

Why response builds gradually

Placeholder: response builds gradually as immune cells expand and differentiate.

Dose 2 Timing Window — 2 to 6 Months

Giving dose 2 within this window is critical for efficacy.

• Month 2: Window opens (earliest allowed)
• Month 6: Window closes (label guidance)
• Still valid: Late dosing (no need to restart series)
• Lower boost: Missed window risk (reduced anamnestic peak)

Why timing matters

Placeholder: the window balances priming maturity against waning response.

Dose 2 Boost Response

The second dose drives a much sharper titer spike.

• ~3–4×: Boost magnitude (vs. dose 1 peak)
• ~4 weeks post-dose 2: Peak timing (anamnestic response)
• ~97%: Zoster efficacy (immunocompetent adults)
• ~91%: PHN efficacy (immunocompetent adults)

Anamnestic boosting mechanism

Placeholder: memory cells from dose 1 drive a faster, larger second response.

Sustained Protection and Immune Status Impact

Long-term titers and efficacy differ by immune status.

• ~10 years: Duration studied (follow-up data)
• ~90%+: Immunocompetent efficacy (through year 4)
• ~68–87%: Immunocompromised efficacy (varies by condition)
• Slow: Titer decline rate (gradual waning)

Immune status effect on durability

Placeholder: immunocompromised patients show a lower, faster-waning titer curve.

Placeholder: monitoring and possible revaccination guidance may apply.